The Syrian civil war may undo the European Union's attempts to appease Hezb'allah, and has revealed how the Iran-backed terrorist organization undermines -- rather than promotes -- Lebanon's interests.

Following the July 2006 war that Hezb'allah provoked with Israel (in which Hezb'allah displayed its anti-ship, anti-tank, and UAV capabilities), UN Security Council Resolution 1701 required that all Lebanese militias disarm. By continuing to possess and acquire weapons since 2006, Hizb'allah has been in nonstop violation of Resolution 1701, but the UN Interim Force in Lebanon can hardly be expected to disarm one of the world's most powerful militias.

Hezb'allah is estimated to have 40-60,000 missiles and rockets, and other arms that many countries lack. To justify its massive arsenal, which exists beyond the control of the Lebanese government, Hezb'allah has relied on its image as a Lebanese organization protecting Lebanese sovereignty. But Hezb'allah's tolerance of repeated attacks on Lebanese citizens and territory by the Syrian army and air force (which bombed the Lebanese village of Arsal last week) completely contradicts Hezb'allah's stated rationale for its deadly arms.

Israel has forcefully responded to each border violation by the Assad regime and thereby provided an effective deterrent that is notably absent from the Lebanese border. Would the Syrian air force and army violate Lebanese sovereignty so frequently if Hezb'allah responded to Syrian violations the way Israel has? Hezb'allah has never even threatened to use (much less actually used) its formidable military force to protect Lebanon's interests against Syrian government incursions.

But Hezb'allah has used its weapons to pursue its own agenda in Syria by joining its Iranian patron in propping up the Assad regime. While the Lebanese government has exercised maximum restraint to avoid embroiling Lebanon in the explosive conflict next door, Hezb'allah has done the exact opposite by openly siding with a tyrant who kills his own people. Like his father Hafez Assad, who in 1982 slaughtered tens of thousands in Hama, Basher Assad has continued the family tradition of brute force to quell dissent using jets, attack helicopters, Scud missiles, and reportedly even poison gas. Hezb'allah has facilitated Assad's butchery with ground forces, training, Iranian-supplied arms and expertise, and other forms of support. Hezb'allah's participation in the Syrian regime's massacres directly jeopardizes the internal stability of Lebanon -- a country whose ethnically diverse components sympathize with different sides of the Syrian conflict. It also invites even more cross-border attacks into Lebanon by effectively widening the theater of combat.

"A state within a state," Hezb'allah has frequently ventured into unwarranted conflicts, dragging the rest of Lebanon into costly wars with Israel and now Syria. But if ordinary Lebanese aren't confronting Hezb'allah, it's because -- after their own bloody civil war (from 1975 to 1990) -- they're afraid to challenge the most lethally-armed faction in the complex tinderbox that is Lebanon. Indeed, Lebanese can't even get justice for the 2005 assassination of their prime minister, Rafiq Hariri. The Special Tribunal for Lebanon, established to investigate the crime, issued arrest warrants against four senior members of Hezb'allah in connection with Hariri's assassination, and they remain free.

But what about the EU? Europe claims to support the Syrian rebels, yet its stubborn refusal to label Hezb'allah what it plainly is -- a terrorist organization -- empowers the Assad-Iran-Hezb'allah alliance fighting those very rebels. Current EU policy allows thousands of Hezb'allah members to conduct vital political and fund-raising activities on European territory, treating Hezb'allah as a Lebanese political and social movement, even though the group has been linked to terror plots on EU soil (Bulgaria and Cyprus), one of which killed an EU citizen.

Germany hosts about 1,000 members of the same terrorist organization that popularized suicide bombings with its 1983 bombing of the U.S. embassy in Beirut (killing 58 Americans and Lebanese), the U.S. Marine barracks (killing 241 American peacekeepers) and the French barracks (killing 58 French soldiers). Hezb'allah was also behind the 1985 hijacking of TWA flight 847, the 1992 bombing of the Israeli Embassy in Argentina (killing 29), the 1994 bombing of a Jewish cultural center in Buenos Aires (killing 85), and the Khobar Towers housing complex in Saudi Arabia (killing 19 U.S servicemen), to list just some of its attacks.

The U.S. and Canada have rightly acknowledged the obvious in designating Hezb'allah a terrorist organization. Bahrain recently became the first Arab country to do so. So why has the European Union failed to blacklist Hezb'allah and halt the terror group's operations on EU soil? In a word: appeasement. France fears Hezb'allah retribution against French peacekeepers in Lebanon, and Germany worries about the many sleeper cells on its territory.

But the EU's unprincipled stand may falter because of two possibilities: 1) Hezb'allah attacks against U.S. or Israeli targets on EU soil could kill enough Europeans to force a confrontation, 2) the EU policy of supporting the Syrian rebels and opposing Iranian nukes may prompt Hizb'allah to target European interests. A serious showdown looms, and the EU would be wise to take the offensive in facing the Hezb'allah threat on its territory.

Noah Beck is the author of The Last Israelis, a doomsday thriller about the Iranian nuclear threat and current geopolitical issues in the Middle East.